<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script type="text/javascript" src="NO5.js">

    </script>
</head>
<body>
    第一个数<input id="num1" type="number" ><br>
    第二个数<input id="num2" type="number" ><br>
    <button onclick="gettext()">+</button>
    <button onclick="add()">-</button>
    <button onclick="test()">×</button>
    <button onclick="ds()">÷</button><br>
    计算结果<input id="result" type="" >
</body>
</html>